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      11-04-2008, 01:53 AM   #42
NASA/PDA Instructor
ace996's Avatar

Drives: E92M3
Join Date: Aug 2008
Location: Long Island

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Looks like a nice product. But the pressure sensor is what I need.

I surmise that any "ram-air" scoop used will not enhance performance due to the large, it is quite big, vent that exits out the hood on the driver's side (the passenger vent is fake). During rain, or after a wash, water flies out that hole from air that is being rammed in the air-box from the two ram-intakes in the front of the car...our driver foglight area, and where these "scoops" go...the radiator location (which is much smaller than our foglight-inlet).

My main thought, is that if the vent out the hood could be modded with a one-way valve, or flapper, or pivoting louvers (as another poster suggested), that we could have a true ram-airbox...but also allow air to be drawn in when there was a neutral or negative pressure inside the airbox dueto engine vacuum/load. That would allow a better 'ram-effect' at speed and not cause the VE to drop, as it did in your "blocking the headlamp inlet" experiment above on your MC. On my prior Ducati, I buzzed open the air inlets (a popular mod for the 996) to allow more air to be ingested at speed...but there was no opening in the was sealed. Most motorcycle builders go to great lengths to have a sealed airbox, where ram-effect is maximized. If you have a hole in the box, the ram effect is not going to do much. I suspect that the hole in the hood is for when there isn't enough air being forced into the box at lower speeds and there is a drop in VE, as you saw in your experiment, because air was being "pulled" into the airbox...instead of being "pushed" from dynamic pressure.
That's why, in my mad-scientist creative opinion, the flapper valve would allow both to happen but would allow an improvement in "ram-effect" by sealing the hood-vent when positive pressure/dynamic pressure was present in the airbox. Did I completely botch that explanation?'s late...

That's why I'd like the see if the vent could be plugged or if it needs a one-way valve/flapper to allow the vent in the hood to be an inlet. If the third inlet shows a negative pressure at high load/rpm, then the flapper is needed...if not, then it can be closed. I'm not really concerned with the effects at anything under 50mph...I'd rather trade low-speed performance for high-speed (I do track my car) performance. But the flapper would accomplish both.

The only other consideraton is the cooling effect of the circulated/dumped air out of the hood...but I'mnot concerned wth that...the airbox will be cool at speed anyway.

Thank you for the suggestion,

"Arcadian, I've fought countless times, yet I've never met an adversary who could offer me what we Spartans call "A Beautiful Death." I can only hope, with all the world's warriors gathered against us, there might be one down there who's up to the task."Μολὼν λαβέ!!

Last edited by ace996; 11-04-2008 at 02:13 AM.